Tailoring the detection sensitivity of graphene based flexible smoke sensors by decorating with ceramic microparticles

The fire risks detection using reliable devices with compact design and ultralow energy consumption has been an important topic of research in the last years. Therefore, this work reports the fabrication and electrical characterization of flexible graphene sensors (FGSs) for smoke detection. For this, a flexible graphene composite with thickness of 1.0 +/- 0.1mm was fabricated using a mold-casting method and sensitized with Ruddlesden Popper perovskite (RPP) and TiO2 micro/nanoparticles for smoke detection purposes. The electrical characterization indicates that the sensors sensitized with the RPP microparticles present faster response times and lower recovery times than those sensitized with TiO2 nanoparticles. The main advantages of these sensors are: 1) They operate with very low power consumption (2-7 mW), and 2) they do not need to be in direct contact with the smoke source or fire source as reported in previous graphene based sensors. Thus, the flexible smoke sensors presented here offer new opportunities to develop a new generation of low cost and compact sensors which can be re-designed in the near future for detecting other types of gases for security purposes or medical applications.